Right now beacons allow permissions to friends, it would be nice to add a public option.
This could be used by shop owners to take custom orders via signs or even for public message boards…hunt announcements, help wanted, etc.
Permission would be for use only.
For that I would suggest a messanging system, which would also give even more pro’s. Public access to interactable stuff (next to doors) should stay limited as it is. Of cause there could be a item to create that you can put into your beacon so that people can leave messages for you, so a mix of “a messanging system” and “beacon orientated gameplay” 
doesn’t just have to apply to signs, it would be great for a community storage as well!
for community usage you still can make a beacon especially for it (even if surrounded by another beacon) and add all of the community as friends. Open for all will allways end in “one guy comes and takes it all”
thats kinda why i left storage out of the discussion to begin with
this is true, as it’s happening right now, I’m the beacon owner for the community storage in the settlement I’m in and it is quite annoying to have to be online at the same time to add everyone as friends.
I know that someone coming in and taking all of something is a problem and expect it to happen. the solution is to have a general mass drop-off area that everyone (or currently whoever has friended me) has access to that can drop off excess or requested materials. The captain or a senior guild member can then move goods from the mass drop-off to the proper section.
This would be a lot easier and simpler to do this rather than set up request baskets for every different material we need.